Configurable hardware logic devices, such as field programmable gate arrays (FPGAs), for example, are increasingly used to execute functionality for host computing devices. Configurable hardware logic devices often require reloading to change the configuration of the devices to perform different functionality. Some configurable hardware logic devices support partial reloading, allowing the configurable hardware logic device to remain on the bus during reconfiguration.
However, in many cases, the configurable hardware logic device interface with a processor of the host device is significantly changed by the reconfiguration. In these cases, registers, bus numbers, interrupts, and/or address space, for example, must be changed, requiring a re-enumeration of the configurable hardware logic device on the bus by the operating system.
Accordingly, in cases in which the functionality of a configurable hardware logic device is significantly changed requiring re-enumeration, the host computing device must perform a reboot. When the host computing device powers back up in the reboot, the operating system will re-enumerate the configurable hardware logic device on the bus. Unfortunately, the rebooting of the host computing device can result in a significant disruption to the performance of the host computing device for users and/or other networked devices.
Additionally, a bus attached to the configurable hardware logic device cannot be used to send the new configuration to the configurable hardware logic device in these cases. Instead, the configurable hardware logic device must be reconfigured during power up of the host computing device. For example, the new configuration can be loaded into non-volatile memory, such as an EEPROM, which is used to load the new configuration when the host computing device powers up. Since new configurations can be fairly large, this method for reloading the configurable hardware logic device takes a significant amount of time, in addition to the time required to reboot the host computing device, which is undesirable.